Thermostatically controlled mixing valve



Patented Aug. 21, 1951 UNITED STATES PATENT OFFICE mannosm nmmQoNTRoL-LED MIXING VALVE Anita-a J Zak, Milwaukee; Wis ApplicationFebruary 6, 1956, scrim-No. 142,590 1 claim. (01. time) This inventionappertams to a thermostatically controlled hot and cold water mixingvalve; and more particularly to a novel means for constructing saidvalve to obtain a positive operation thereof.

One of the primary objects of my invention is to provide a hot and coldwater or other liquid mixing valve which will be durable and efiicientin use, one that will be simple to manufacture, one which can be placedupon the market at a reasonable price and one which will be of an ex;-ceptional compact nature so as to occupy a minimum amount of space in awall or the like.

Another salient object of my invention isjto provide a valve casingembodying. spaced parallel hot and cold water inlets, with a singlevalve shaft extending through the inlets having secured directly theretofor movement therewith butterfly valves for the hot and cold waterinlets, whereby any movement of the shaft directly affects the positionof the butterfly valves.

A further important object of the avenues is the provision of a manuallyadjustable control shaft disposed in front'of' and parallel with thevalve shaft, with a spiral bimetallic spring (men mostat) connectingsaid shafts together,- said thermostat being located adjacent to theoutlet for the mixedhot and-cold water, and in the: path of the flow ofsaid mixed-water to the outlet;

A still further object of the invention is the provision of novelmeansin the valve casing for preventing back pressure in the" hot andcoldwater conduit pipes; andto reduce back-pressureon the butterflyvalves, so as to insure ease and positive operation of the valve shaftand butterfly valves.

A still further object of the invention is the provision of means forholding the manually oper able shaft in a selected temperaturecontrolling position against accidental movement and against movementunder influence of the thermostat.

With these and other objects in view, the invention consists in thenovel construction, arrangement and formation of parts, as will behereinafter more specifically described and claimed and illustrated inthe accompanying drawing, in which drawing:

Figure 1 is a longitudinal sectional view through my improved hot andcold liquid mixing valve.

Figure 2 is a front elevational view of the hot and cold water mixingvalve.

Figure 3 is a, transverse sectional view through the mixing valve takenon the line 3, 3 of Figure 1, looking in the direction of the arrows.

Figure 4 is a fragmentary detail horizontal sectional view taken on theline 4, 4 of Figure 1,

looking in the direction of the arrows and illus trating one er thebutterfly valves.

Referring to the drawing indetail, wherein similar reference charactersdesignate corresponding parts throughout the several views, the letter Mgenerally indicates my novel mixing valve, and the same includes a valvecasing '5 which can be of a general cylindrical formin cross section.-The valve casing is provided with a lo'n= gitudinal way 6' for thepassage of hot and cold water, and communicating with this assagewayadjacent to the front of the casing is a mixing chamber l. Communicatingwith the passageway 6 at one side of the chamber 1 are the sp'a'c'edparallel cold and hot water inlets 8 and 9'. Communicating with thechamber I is the'nii'xe'dhot and cold water outlet [0, audit is to benoted that the inlets 3 and 9 and the outlet [0" are arranged in spacedparallel relation, but obviously, a different angle for the outlet HI-can be bad if such should be desired. The frdnt or the casing: 5 ispreferably left open for ease in as sembling various parts, and thefront of the casing is normally closed by a front plate II which can beof an ornamental character. Obviously. a gasket or other packing' i2 canbe placed 196- tween the front plate II and the body of the casing 5; I

Extending through the inlets 8 and 9 is arotat= able'valve shaft [3, andthis valve shaft extends diametrically'through' the inlets and issupported by certain walls of the casing for free turning movement. 7 I

Rigidly secured-to the shaft 13 for turning movement therewith arebutterfly valves l4 and [5. The valve l4 controls the how of cold waterthrough the inlet 8 and the valve l5 controls the flow of hot waterthrough the inlet 9, and these valves are preferably at right angles toone another. The forward end of the shaft I3 extends into the chamber 1and has secured thereto the crank arm B6. The outer end of the armterminates in a slotted right angularly extending leg IT for a purposewhich will be later set forth.

Rotatably carried by the front cover plate Ii is the manually controlledadjustment shaft [8, and this shaft can be disposed just off center fromthe shaft I3, and the adjustment shaft I8 terminates in close proximityto the front end of the shaft [3 and the crank arm [6. A packing glandl9 can be provided for the shaft [8 to prevent leakage of water aroundthe same. The outer end of the shaft I8 carries a manipulating hand knob20, which is also, preferably, of an ornamental character. Formed on theknob is an indicating pointer 2|, for travelling movement over the frontface of the cover plate II, and a scale 22 marked thereon. The pointer2| can also carry a latch tooth 23. This tooth travels over a series ofindentations 24, and the tooth engaging the walls of the indentationprevent accidental rotation of the adjustment shaft I8.

A spiral bimetallic spring 25 (thermostat) connects the shafts I8 and I3together, and the inner end of the spring 25 is firmly anchored to theshaft I8, as at 26. The outer end of the spring terminates in a finger21, and this finger is connected to the leg I! of the crank arm I8. Inorder to maintain the pointer M in proper position, a spring 28 can becoiled around the shaft I8, and one end of the spring can bear againstthe plate II and the other end of the spring against the pin 29 orwasher carried by said shaft.

By referring to Figure 1, it can be seen that the thermostat 25 isdisposed directly within the mixing chamber I and in close proximity tothe outlet I0, and, consequently, the mixed water from the inlets 8 and9 flow directly past the thermostat to the outlet, and the temperatureof the mixed water will directly affect the thermostat. The thermostat25 is arranged to maintain the temperature value of the mixed waterconstant. If the temperature of the water drops, the spiral willcontract and rotate the crank arm I6 and shaft I3 in a direction tendingto open butterfly valve I5 and to close butterfly valve I4. If thetemperature of the water increases, a reverse action occurs, and thespiral will expand and will turn the shaft I3 and move the valve I5toward a closed position, and the valve I4 toward an open position. Byturning the knob 20, the position of the shaft I8 can be changed so asto alter the position of the inner convolutions of the thermostat, andhence, by setting the knob at a selected point, a certain temperature ofwater can be had. Obviously, a mixed water conduit pipe 30 communicateswith the outlet I0 and a cold water conduit pipe 3I communicates withthe inlet 8, likewise, a hot water conduit pipe 32 communicates with theinlet 9.

In order to prevent back pressure of water through the pipes 3| and 32,and to relieve undue pressure on the valves I4 and I5, I prefer toprovide the following construction:

Valve cages 33 are disposed in the inlets 8 and 9 on the inlet side ofthe valves, and these cages 33 carry spring pressed one-way check valvebodies 34. Obviously, water flowing through the conduits 3| and 32 intothe valve casing will unseat the check valve bodies, but that watertending to flow in the reversed direction will seat said valve bodies.The inlets 8 and 9 are slightly restricted, as at 35, below the valvesl4 and I5, and this restriction also lessens back pressure on the valvesI4 and I5.

While I have illustrated a hand knob 28, it is to be understood that aremote control device can be employed for adjusting the shaft I8.

Changes in details may be made Without departing from the spirit or thescope of this invention, but what I claim as new is:

A thermostatically controlled water mixing valve comprising a housinghaving a longitudinal passageway and spaced parallel inlets communi--eating with the passageway for cold and hot water, said casing alsohaving a mixing chamber for hot and cold water communicating with thelongitudinal passage and an outlet communicating with the chamber formixed hot and cold water, a rotatable valve shaft in said casingextending diametrically through the inlets, a butterfly valve for eachinlet secured directly to the valve shaft for turning movementtherewith, a crank arm on the valve shaft disposed in the chamber, anadjustment shaft rotatably carried by the casing disposed in front ofthe valve shaft and having its forward end extending beyond said casing,a handle for turning the shaft, and a thermostat, including a spiralbimetallic spring, having its inner end connected to the adjustmentshaft and its outer end connected to the crank arm.

ALPHONSE J. ZAK.

Country Date France June 27, 1925 Number Number

